CN-122009124-A - Locking mechanism of electromechanical service brake, operation method of locking mechanism and service brake

Abstract

Locking mechanism (01) for locking a movement of an electromechanical service brake, in particular a release movement for reducing the pressing force of two friction partners, which locking mechanism is preferably used in a motor vehicle, in particular in a passenger vehicle, the locking mechanism (01) comprising a locking catch (03) which is arranged to engage in a locking member (02) of the electromechanical service brake in a locked state of the locking mechanism (01) for locking the movement of the electromechanical service brake and to release the locking member (02) in an unlocked state of the locking mechanism (01), the locking mechanism (01) further comprising an actuator (04), in particular a linear actuator (05) or a linear drive, for moving the locking catch (03) between the locked state and the unlocked state.

Inventors

• F. Beller-Miller

Assignees

• 罗伯特·博世有限公司

Dates

Publication Date

20260512

Application Date

20251111

Priority Date

20241112

Claims (10)

1. 1. A locking mechanism (01) for locking a movement of an electromechanical service brake, in particular a release movement for reducing the pressing force of two friction partners, the locking mechanism preferably being used in a motor vehicle, in particular in a passenger vehicle, the locking mechanism (01) comprising a locking catch (03) which is arranged to engage in a locking member (02) of the electromechanical service brake in a locked state of the locking mechanism (01) for locking the movement of the electromechanical service brake and to release the locking member (02) in an unlocked state of the locking mechanism (01), the locking mechanism (01) further comprising an actuator (04), in particular an electromagnetic linear actuator (05) or a linear drive, for moving the locking catch (03) between the locked state and the unlocked state, It is characterized in that the method comprises the steps of, The locking mechanism (01) comprises a lever mechanism (06), wherein the lever mechanism (06) is dimensioned in such a way that the actuator (04) is connected to the locking catch (03), in particular in a mass-compensated manner, wherein the lever length (r 1) of the lever mechanism (06) that is effective for the locking catch (03) and the lever length (r 2) of the actuator (04) are in a ratio to one another such that the inertial forces (F1, F2) acting on the locking catch (03), the actuator (04) and/or the lever mechanism (06) due to an external acceleration (a) acting on the locking mechanism (01) are balanced with one another, so that the locking catch (03) is held in the unlocked state independently of the magnitude and/or direction of the external acceleration (a) from the unlocked state.
2. 2. The locking mechanism (01) for an electromechanical service brake according to claim 1, It is characterized in that the method comprises the steps of, The locking mechanism (01) comprises a rocker arm (07), the rocker arm (07) being rotatably supported about a rotational axis (08), the locking latch (03) and the actuator (04) being articulated on different sides of the rocker arm (07) about the rotational axis (08) such that inertial forces (F1, F2) acting on the locking latch (03), the actuator (04) and the rocker arm (07) due to external accelerations (a) generate moments (M1, M2) that are opposite in direction about the rotational axis (08).
3. 3. The locking mechanism (01) for an electromechanical service brake according to claim 2, It is characterized in that the method comprises the steps of, The lever length (r 1) of the rocker arm (07) which is effective for the locking catch (03) and the lever length (r 2) which is effective for the actuator (04) are in a ratio to one another such that the torques (M1, M2) which are opposite in direction produce a torque balance about the rotational axis (08).
4. 4. Locking mechanism (01) for an electromechanical service brake according to any of the previous claims, It is characterized in that the method comprises the steps of, The locking mechanism (01) comprises a damping element (09) which dampens the movement of the locking mechanism (01) and is in particular articulated at the locking catch (03), the actuator (04) or the lever mechanism (06).
5. 5. Locking mechanism (01) for an electromechanical service brake according to any of the previous claims, It is characterized in that the method comprises the steps of, The locking mechanism (01) comprises a spring element (10) which preloads the locking mechanism (01) towards the unlocked state and is in particular articulated at the locking latch (03), the actuator (04) or the lever mechanism (06).
6. 6. The locking mechanism (01) for an electromechanical service brake according to claim 5, It is characterized in that the method comprises the steps of, The spring element (10) has a spring force which is 1.3 times, preferably 1.2 times, more preferably 1.1 times the required minimum mechanical restoring force due to tolerances and/or friction.
7. 7. Locking mechanism (01) for an electromechanical service brake according to any of the previous claims, It is characterized in that the method comprises the steps of, The direction of movement (D) of the locking latch (03) and the direction of movement (E) of an actuator (04) for moving the locking latch (03) between the unlocked state and the locked state are arranged parallel to each other.
8. 8. The locking mechanism (01) for an electromechanical service brake according to any one of claims 1 to 6, It is characterized in that the method comprises the steps of, The direction of movement (D) of the locking catch (03) and the direction of movement (E) of an actuator (04) for moving the locking catch (03) between the unlocked state and the locked state are arranged at an angle (b) to each other, wherein an angular bisector (G) of the angle (b) is arranged parallel to a main direction of action (H) of the external acceleration (a).
9. 9. Electromechanical service brake, in particular having the function as a parking brake, preferably for use in a motor vehicle, in particular a passenger car, comprising a locking mechanism (01) according to any one of claims 1 to 8.
10. 10. Method for operating a locking mechanism (01), which locking mechanism (01) is intended for locking a movement of an electromechanical service brake, in particular for reducing a release movement of a pressing force of two friction partners, which locking mechanism is preferably used in a motor vehicle, in particular in a passenger vehicle, which locking mechanism (01) comprises a locking catch (03) which is arranged to engage in a locking member (02) of the electromechanical service brake in a locked state of the locking mechanism (01) for locking the movement of the electromechanical service brake and to release the locking member (02) in an unlocked state of the locking mechanism (01), which locking mechanism (01) further comprises an actuator (04), in particular a linear actuator (05) or a linear drive for moving the locking catch (03) between the locked state and the unlocked state, It is characterized in that the method comprises the steps of, The inertial forces (F1, F2) acting on the locking catch (03), the actuator (04) and/or the lever mechanism (06) due to an external acceleration (a) acting on the locking mechanism (01) are balanced by a lever length (r 1) of the lever mechanism (06) which is effective for the locking catch (03) and a lever length (r 2) of the actuator (04) such that the locking catch (03) is held in the unlocked state independently of the magnitude and/or direction of the external acceleration (a) starting from the unlocked state, wherein the lever mechanism (06) connects the actuator (04) to the locking catch (03), and the lever mechanism (06) is dimensioned in particular in a mass-compensating manner to connect the actuator (04) to the locking catch (03).

Description

Locking mechanism of electromechanical service brake, operation method of locking mechanism and service brake Technical Field The present invention relates to a locking mechanism for use in an electromechanical service brake, preferably for a motor vehicle. The invention also relates to an electromechanical service brake having a locking mechanism and to a method for operating a locking mechanism. Background Various solutions are known in the prior art for implementing a parking brake function in an electromechanical service brake. Document DE 10 224 A1 describes a method for actuating a parking brake system which is integrated into an electromechanical service brake. In order to actuate the parking brake, the electromechanical service brake is actuated by means of its brake actuator when the vehicle is parked, and is latched in the actuated state by means of a locking mechanism, so that a release movement is prevented. The locking mechanism includes a locking pawl and a ratchet coupled to a brake actuator. For locking, the movement of the locking pawl is released by means of the catch and then the locking pawl is brought into engagement with the ratchet wheel. Unlocking of the locking pawl and manipulation of the locking pawl is accomplished by separate electromagnets. The catch ensures that the locking pawl does not accidentally engage in the ratchet, for example, due to vibrations during travel. The disadvantage of this solution is the increased complexity, since two actuators are required to operate the locking mechanism, which results in increased demands on cabling, control technology and installation space. Document DE 10 234 848 shows an alternative locking mechanism for securing an electromechanical service brake. The locking latch is linearly movable to latch into the ratchet. To lock the ratchet, the linear actuator is manipulated so that the locking latch moves against the spring force of the return spring to a position that locks the ratchet. The spring force is selected to be large enough to reliably prevent unintended movement of the locking latch when the mechanism is subjected to external acceleration. A powerful linear actuator is required to overcome such a powerful spring force when activating the locking mechanism, which is disadvantageous in terms of cost, installation space, mass and electrical power requirements. The object of the present invention is to provide a locking mechanism, an electromechanical service brake and a method for operating a locking mechanism which overcome the above-mentioned disadvantages of the prior art. Disclosure of Invention The locking mechanism according to the invention with the features of claim 1, the electromechanical service brake with the features of claim 9 and the method for operating the locking mechanism according to the invention with the features of claim 10 have the advantage that an external acceleration does not cause the locking mechanism to accidentally transition to the locked state. In this case, it is advantageous if the mechanical design of the locking mechanism according to the invention is simple, in particular without additional actuators being required. Furthermore, no particularly powerful actuator is required, which advantageously reduces the effort associated with the size of the electronic and/or electrical components. The locking mechanism according to the invention is therefore advantageously compact and lightweight. Thus, the electromechanical service brake with the locking mechanism according to the invention is also advantageously simple and compact in construction. The locking mechanism according to the invention for locking a movement of an electromechanical service brake comprises a locking catch, wherein the movement is in particular a release movement for reducing the pressing force of two friction partners, the locking mechanism being preferably used in a motor vehicle, in particular in a passenger vehicle, the locking catch being arranged to engage in a locking element of the electromechanical service brake in a locked state of the locking mechanism for locking the movement of the electromechanical service brake and to release the locking element in an unlocked state of the locking mechanism. The locking mechanism further comprises an actuator, in particular a linear actuator or a linear drive of electromagnetic type, for moving the locking latch between the locked state and the unlocked state. According to the invention, the locking mechanism comprises a lever mechanism, which is dimensioned in particular in a mass-compensating manner to connect the actuator to the locking catch, wherein the lever length of the lever mechanism effective for the locking catch and the lever length effective for the actuator are in a ratio to one another such that, as a result of an external acceleration acting on the locking mechanism, the inertial forces acting on the locking catch, the actuator and/or the lever mechanism balance